If this is the one I think it is: helmets make cycling seem dangerous and fewer people do it. More cyclists = safer cycling so, lidless -> more cyclists -> safer cycling than exists today with a helmet.

I wear a helmet and I ride a bike so the culture of fear that he talks about hasn't affected me. I think rather than saying don't wear a helmet we should tell of all the health and societal benefits of riding whether you wear a helmet or not. Don't let wearing a helmet keep you from riding a bike.